 /*******************************************************************************
  * Copyright (c) 2000, 2005 IBM Corporation and others.
  * All rights reserved. This program and the accompanying materials
  * are made available under the terms of the Eclipse Public License v1.0
  * which accompanies this distribution, and is available at
  * http://www.eclipse.org/legal/epl-v10.html
  *
  * Contributors:
  * IBM Corporation - initial API and implementation
  *******************************************************************************/
 package org.eclipse.core.resources.team;

 import java.net.URI ;
 import org.eclipse.core.filesystem.EFS;
 import org.eclipse.core.filesystem.URIUtil;
 import org.eclipse.core.internal.resources.InternalTeamHook;
 import org.eclipse.core.resources.*;
 import org.eclipse.core.runtime.*;

 /**
  * A general hook class for operations that team providers may be
  * interested in participating in. Implementors of the hook should provide
  * a concrete subclass, and override any methods they are interested in.
  * <p>
  * This class is intended to be subclassed by the team component in
  * conjunction with the <code>org.eclipse.core.resources.teamHook</code>
  * standard extension point. Individual team providers may also subclass this
  * class. It is not intended to be subclassed by other clients. The methods
  * defined on this class are called from within the implementations of
  * workspace API methods and must not be invoked directly by clients.
  * </p>
  *
  * @since 2.1
  */
 public abstract class TeamHook extends InternalTeamHook {
     /**
      * The default resource scheduling rule factory. This factory can be used for projects
      * that the team hook methods do not participate in.
      *
      * @see #getRuleFactory(IProject)
      * @see #setRuleFactory(IProject, IResourceRuleFactory)
      * @since 3.0
      */
     protected final IResourceRuleFactory defaultFactory = new ResourceRuleFactory();

     /**
      * Creates a new team hook. Default constructor for use by subclasses and the
      * resources plug-in only.
      */
     protected TeamHook() {
         super();
     }

     /**
      * Returns the resource scheduling rule factory that should be used when workspace
      * operations are invoked on resources in that project. The workspace will ask the
      * team hook this question only once per project, per session. The workspace will
      * assume the returned result is valid for the rest of that session, unless the rule
      * is changed by calling <code>setRuleFactory</code>.
      * <p>
      * This method must not return <code>null</code>. If no special rules are required
      * by the team hook for the given project, the value of the <code>defaultFactory</code>
      * field should be returned.
      * <p>
      * This default implementation always returns the value of the <code>defaultFactory</code>
      * field. Subclasses may override and provide a subclass of <code>ResourceRuleFactory</code>.
      *
      * @param project the project to return scheduling rules for
      * @return the resource scheduling rules for a project
      * @see #setRuleFactory(IProject, IResourceRuleFactory)
      * @see ResourceRuleFactory
      * @since 3.0
      */
     public IResourceRuleFactory getRuleFactory(IProject project) {
         return defaultFactory;
     }

     /**
      * Sets the resource scheduling rule factory to use for resource modifications
      * in the given project. This method only needs to be called if the factory has changed
      * since the initial call to <code>getRuleFactory</code> for the given project
      * <p>
      * The supplied factory must not be <code>null</code>. If no special rules are required
      * by the team hook for the given project, the value of the <code>defaultFactory</code>
      * field should be used.
      * <p>
      * Note that the new rule factory will only take effect for resource changing
      * operations that begin after this method completes. Care should be taken to
      * avoid calling this method during the invocation of any resource changing
      * operation (in any thread). The best time to change rule factories is during resource
      * change notification when the workspace is locked for modification.
      *
      * @param project the project to change the resource rule factory for
      * @param factory the new resource rule factory
      * @see #getRuleFactory(IProject)
      * @see IResourceRuleFactory
      * @since 3.0
      */
     protected final void setRuleFactory(IProject project, IResourceRuleFactory factory) {
         super.setRuleFactory(project, factory);
     }

     /**
      * Validates whether a particular attempt at link creation is allowed. This gives
      * team providers an opportunity to hook into the beginning of the implementation
      * of <code>IFile.createLink</code>.
      * <p>
      * The implementation of this method runs "below" the resources API and is
      * therefore very restricted in what resource API method it can call. The
      * list of useable methods includes most resource operations that read but
      * do not update the resource tree; resource operations that modify
      * resources and trigger deltas must not be called from within the dynamic
      * scope of the invocation of this method.
      * </p><p>
      * This method should be overridden by subclasses that want to control what
      * links are created. The default implementation of this method allows all links
      * to be created.
      * </p>
      *
      * @param file the file to be linked
      * @param updateFlags bit-wise or of update flag constants
      * (only ALLOW_MISSING_LOCAL is relevant here)
      * @param location a file system path where the file should be linked
      * @return a status object with code <code>IStatus.OK</code>
      * if linking is allowed, otherwise a status object with severity
      * <code>IStatus.ERROR</code> indicating why the creation is not allowed.
      * @see org.eclipse.core.resources.IResource#ALLOW_MISSING_LOCAL
      */
     public IStatus validateCreateLink(IFile file, int updateFlags, IPath location) {
         return Status.OK_STATUS;
     }

     /**
      * Validates whether a particular attempt at link creation is allowed. This gives
      * team providers an opportunity to hook into the beginning of the implementation
      * of {@link IFile#createLink(URI, int, IProgressMonitor) }
      * <p>
      * The implementation of this method runs "below" the resources API and is
      * therefore very restricted in what resource API method it can call. The
      * list of useable methods includes most resource operations that read but
      * do not update the resource tree; resource operations that modify
      * resources and trigger deltas must not be called from within the dynamic
      * scope of the invocation of this method.
      * </p><p>
      * This method should be overridden by subclasses that want to control what
      * links are created. The default implementation of this method allows all links
      * to be created.
      * </p>
      *
      * @param file the file to be linked
      * @param updateFlags bit-wise or of update flag constants
      * (only ALLOW_MISSING_LOCAL is relevant here)
      * @param location a file system URI where the file should be linked
      * @return a status object with code <code>IStatus.OK</code>
      * if linking is allowed, otherwise a status object with severity
      * <code>IStatus.ERROR</code> indicating why the creation is not allowed.
      * @see org.eclipse.core.resources.IResource#ALLOW_MISSING_LOCAL
      * @since 3.2
      */
     public IStatus validateCreateLink(IFile file, int updateFlags, URI location) {
         //forward to old method to ensure old hooks get a chance to validate in the local case
 if (EFS.SCHEME_FILE.equals(location.getScheme()))
             return validateCreateLink(file, updateFlags, URIUtil.toPath(location));
         return Status.OK_STATUS;
     }

     /**
      * Validates whether a particular attempt at link creation is allowed. This gives
      * team providers an opportunity to hook into the beginning of the implementation
      * of <code>IFolder.createLink</code>.
      * <p>
      * The implementation of this method runs "below" the resources API and is
      * therefore very restricted in what resource API method it can call. The
      * list of useable methods includes most resource operations that read but
      * do not update the resource tree; resource operations that modify
      * resources and trigger deltas must not be called from within the dynamic
      * scope of the invocation of this method.
      * </p><p>
      * This method should be overridden by subclasses that want to control what
      * links are created. The default implementation of this method allows all links
      * to be created.
      * </p>
      *
      * @param folder the file to be linked
      * @param updateFlags bit-wise or of update flag constants
      * (only ALLOW_MISSING_LOCAL is relevant here)
      * @param location a file system path where the folder should be linked
      * @return a status object with code <code>IStatus.OK</code>
      * if linking is allowed, otherwise a status object with severity
      * <code>IStatus.ERROR</code> indicating why the creation is not allowed.
      * @see org.eclipse.core.resources.IResource#ALLOW_MISSING_LOCAL
      */
     public IStatus validateCreateLink(IFolder folder, int updateFlags, IPath location) {
         return Status.OK_STATUS;
     }

     /**
      * Validates whether a particular attempt at link creation is allowed. This gives
      * team providers an opportunity to hook into the beginning of the implementation
      * of {@link IFolder#createLink(URI, int, IProgressMonitor)}
      * <p>
      * The implementation of this method runs "below" the resources API and is
      * therefore very restricted in what resource API method it can call. The
      * list of useable methods includes most resource operations that read but
      * do not update the resource tree; resource operations that modify
      * resources and trigger deltas must not be called from within the dynamic
      * scope of the invocation of this method.
      * </p><p>
      * This method should be overridden by subclasses that want to control what
      * links are created. The default implementation of this method allows all links
      * to be created.
      * </p>
      *
      * @param folder the file to be linked
      * @param updateFlags bit-wise or of update flag constants
      * (only ALLOW_MISSING_LOCAL is relevant here)
      * @param location a file system path where the folder should be linked
      * @return a status object with code <code>IStatus.OK</code>
      * if linking is allowed, otherwise a status object with severity
      * <code>IStatus.ERROR</code> indicating why the creation is not allowed.
      * @see org.eclipse.core.resources.IResource#ALLOW_MISSING_LOCAL
      * @since 3.2
      */
     public IStatus validateCreateLink(IFolder folder, int updateFlags, URI location) {
         //forward to old method to ensure old hooks get a chance to validate in the local case
 if (EFS.SCHEME_FILE.equals(location.getScheme()))
             return validateCreateLink(folder, updateFlags, URIUtil.toPath(location));
         return Status.OK_STATUS;
     }
 }

